A typical cigarette consists of a tobacco rod, which is wrapped with a cigarette paper. In many cases, cigarettes are also equipped with a filter, typically made from cellulose acetate, which is wrapped with a filter wrapping paper and is additionally wrapped on the outside with a tipping paper, which is slightly longer than the filter and thus connects the filter to the tobacco rod wrapped with the cigarette paper. Such cigarettes are usually consumed by burning the tobacco and the smoke created thereby is inhaled by the smoker.
Alternative smoking articles do not burn the tobacco but just heat it, wherein an aerosol is released which is inhaled by the smoker. It is assumed that the aerosol of such smoking articles contains less harmful substances than the smoke of conventional cigarettes. Instead of tobacco, other aerosol-generating materials can also be used. Depending on the construction of these smoking articles, a wrapping paper can also be required for such smoking articles, which wraps the tobacco or the aerosol-generating material or other parts of the smoking article.
There are many technical requirements for a wrapping paper for smoking articles, in particular regarding the air permeability, the diffusion capacity, but also regarding optical requirements such as whiteness, color and opacity. The selection of possible raw materials for such wrapping papers is often subject to legal restrictions, for which reason the manufacturer of such wrapping papers is restricted in the design of the wrapping paper.
Apart from technical requirements for the wrapping paper, commercial considerations can also play a role in the design of the wrapping paper. The manufacture of paper in general and of wrapping papers for smoking articles in particular needs a lot of energy and, to some extent, expensive raw materials.
Wrapping papers for smoking articles typically contain pulp fibers. These pulp fibers are refined in refiners during the manufacture of the wrapping paper. This means that by mechanically loading the pulp fibers, individual fibers or fibrils of the fiber bundles are exposed. Thus, a larger surface area and more options are available to connect the individual pulp fibers to each other by hydrogen bonds during paper production. This provides the paper with tensile strength, but it also influences its air permeability. In general, more intensive refining of the pulp fibers leads to a higher tensile strength of the paper but to a lower air permeability. This refining process is energy-intensive and thus also expensive.
Pulp fibers are differentiated into long-fiber pulp, which is typically sourced from coniferous trees like spruce, pine or larch, and short-fiber pulp, which is typically sourced from deciduous trees, like beech, birch, eucalyptus, poplar or aspen. In general, long-fiber pulp is more expensive than short-fiber pulp and has to be refined with more energy outlay than short-fiber pulp. In wrapping papers for smoking articles, short-fiber pulp is generally used unrefined.
A further important kind of pulp fibers for wrapping papers for smoking articles are pulp fibers that are not sourced from trees, but for example from flax, hemp, sisal, aback jute or cotton. These pulp fibers can replace the long-fiber pulp regarding their technical effects in the wrapping paper because of their length and tensile strength, but they are even more expensive than long-fiber pulp.
A further important kind of pulp fibers for wrapping papers for smoking articles are pulp fibers that are sourced from esparto grass. These pulp fibers provide the wrapping paper with more volume and lower density and for their technical effects in the wrapping paper can be used as an alternative to short-fiber pulp.
According to the accepted teachings of the prior art, wrapping papers for smoking articles need to contain long-fiber pulp or pulp fibers with comparable technical effect, so that the wrapping paper has a sufficient tensile strength for the manual or machine production of smoking articles. The fraction of long-fiber pulp in the total pulp in wrapping papers for smoking articles is, according to the prior art, at least 20% and typically between 25% and 70%. This causes the production of wrapping papers for smoking articles to be expensive.
Because of the high and generally increasing taxes and fees with which smoking articles are burdened, there is an interest in the industry in producing the components of smoking articles more inexpensively, so that smoking articles can still be offered to the consumer at an acceptable price.
Thus, there is an interest in the industry in producing wrapping paper for smoking articles with less cost outlay for energy and raw materials.